The present invention relates to a practice projectile free of any explosive or bursting charge, adapted for shooting from aircraft against ground targets or for other kinds of practice shooting. The projectile comprises a hollow shell, a projectile base and a nose portion which engages the shell along a circumferential partition therebetween.
Practice shooting from aircraft against ground targets is partly performed from a relatively small height. The shooting partly takes place against targets in such a small distance ahead of the aircraft that the aircraft cannot avoid passing over the target area. In order to reduce the costs of the practice shooting, projectiles without any explosive or blasting charge are normally used, which means that the projectile is not necessarily broken up into small fragments in the target. Consequently, there is a great danger that ricochets of a relatively large size can be returned upwardly from the target area, and this will happen just in the period when the aircraft, having shot the projectile or projectiles passes over the target area. The aircraft, therefore, is in danger of being hit by the ricochets. The ricochets can comprise complete projectiles or large fragments thereof, and the aircraft hull can be seriously damaged and the crew can be in great danger. This problem may be avoided by not flying below a certain minimum height which is larger than the height which the ricochets can reach, but this means that the practice shooting will not be very realistic, because the shooting must cease at such a great distance from the target that the shooting does not correspond to shooting by use of live ammunition. When live ammunition is used, the projectiles will be broken into small fragments in the target area, and the fragments can only return to a small height, without causing any danger to the aircraft.
Also, by other kinds of practice shooting, it may be desirable or necessary to ensure that the range or height of ricochets is limited, for instance in order that they do not spread beyond the boundary of a shooting field.
Different solutions of the problem of ricochetting practice projectiles have been proposed. Projectiles have been made from pressed iron shavings, in order to pulverize upon impact in a target. This solution involves the problem that the projectiles may pulverize during firing from a weapon, due to the large acceleration forces to which the projectiles are subjected. On the other hand, if the projectiles are manufactured with a large or reasonable degree of safety against pulverizing during firing, the projectiles may not even pulverize upon impact in the target. Another attempt consists of making practice projectiles partly or entirely of plastics. This solution leads to a problem with respect to the mass of the projectiles relative to live projectiles. It is desirable that the practice projectiles should have approximately the same mass as corresponding live projectiles, taking into account the ballistic properties. Moreover, the plastics may be overheated or melt in hot gun barrels. This is a safety problem. It must be taken into consideration that the shooting may take place with a very high firing rate (automatic weapons) and consequently with a high generation of heat.
U.S. Pat. No. 146,036 describes a subcaliber projectile having a mainly massive projectile body with weakening portions which cause splitting up of the projectile body. The projectile does not comprise any hollow shell or a separate nose portion.